Observations of highly ionized species (O VI, C IV, N V, Si
IV ) in the interstellar medium (ISM) indicate the existence
of substantial amounts of plasma at Temperatures of T~
105. To explain the line ratios observed, it has been
proposed to be the result of mixing by turbulence at the
interfaces between hot (T~106) and warm
(T~104) media. In addition, the the ISM is
magnetized. And the magnetic field is expected to be a
controlling factor that can suppress the instabilities that
lead to the onset of turbulence at such interfaces. We
present results of numerical simulations of turbulent mixing
layers, using a MHD code with radiative cooling. With a more
complete exploration of parameter space, this work will
provide more reliable diagnostics of turbulent mixing layers
than those available today.